©
Diltiazem is a Calcium Channel Blocker (CCB) and is used to
treat hypertension, to control angina and to manage certain arrhythmia.
©
Diltiazem is a potent vasodilator
of coronary and peripheral vessels and it reduces peripheral resistance and
afterload. Diltiazem decreases heart muscle contractility (Negative Inotropy),
the heart rate (Negative Chronotropy) by slowing sinoatrial node and conductivity
through A-V node (Negative Dromotropy) which all result in reduction of
oxygen consumption by the heart, reducing angina symptoms. The blood pressure is
also be reduced by these effects causing less blood to be pumped out.
©
Diltiazem can interact significantly with drugs such as Cisapride, Colchicine, Lomitapide, Erythromycin,
Amiodarone, Clopidogrel, Beta blockers, Droperidol, Dantrolene, Lacosamide, Clonidine,
Fingolimod, CYP3A4 Inhibitors, CYP3A4 Inducers, CYP3A4 substrates and P-gp Substrates.
© Concomitant use of Diltiazem and Cisapride is
contraindicated due to elevated risk of
cardiotoxicity (QT prolongation, Torsades de pointes, cardiac arrest).
© It is contraindicated
to use Diltiazem along with colchicine in patients with
renal or hepatic impairment, due to increased risk of colchicine toxicity
(Neuromuscular toxicity, etc).
© Use of Diltiazem in patients taking Lomitapide
is contraindicated due to the inhibition
of CYP3A4-mediated metabolism of Lomitapide.
© Monitor
QT interval, if Diltiazem and Erythromycin used concurrently.
© Coadministration of Diltiazem and
Amiodarone should be avoided in patients with sick sinus syndrome or
partial AV block, due to elevated risk of Bradycardia, Atrioventricular block
and/or Sinus arrest.
© The patients should be monitored
for loss of Clopidogrel efficacy, when it is coadministered with
Diltiazem.
© Use of Diltiazem in patients taking Beta
blockers, warrants careful monitoring
of cardiac function and blood pressure.
© Droperidol should be administered with
extreme caution in patients taking Diltiazem.
© Monitor blood pressure and serum
potassium, if Diltiazem is used concurrently with Dantrolene.
© Obtain ECG prior to treatment and
following dose titration, if concurrent therapy of Diltiazem and Lacosamide
is required.
© Heart rate should be monitored,
when Clonidine and diltiazem are administered concurrently.
© Continuous overnight ECG
monitoring is recommended after the first dose of Fingolimod, if
concomitant use with Diltiazem is required.
© The drug levels and adverse
effects of Diltiazem should be monitored closely, when it is coadministered
with CYP3A4 inhibitors such as Clarithromycin, Ceritinib, Atazanavir,
etc.
© Monitor patients for loss of
efficacy, if Diltiazem is used concurrently with CYP3A4 inducers such as
Carbamazepine, St.John’s wort, etc.
© Closely monitor for CYP3A4
substrates associated adverse events, if Diltiazem and CYP3A4 substrates such
as Simvastatin, Atorvastatin, Lovastatin, Apixaban, Domperidone, Donepezil,
Dronedarone, Clozapine, Fentanyl, Hydrocodone, Piperaquine, Erlotinib,
Nilotinib, Crizotinib, Bosutinib, Ibratinib, Doxorubicin, Simeprevir,
Lurasidone, Ranolazine, Eplerenone, Everolimus, Aripiprazole, Eliglustat,
Cilostazol, Tolvaptan, Ivabradine, etc. are coadministered.
© Diltiazem inhibits the efflux
transport of P-gp substrates such as Dabigatran, Apixaban, Everolimus,
Vincristine, Nilotinib, Afatinib, Bosutinib, Trabectedin, Ombitasvir,
Simeprevir, Dasabuvir, Paritaprevir, Topotecan, etc.
© Use caution and monitor the
patient for signs and symptoms of increased exposure of P-gp substrates,
when Diltiazem and P-gp substrates such as Dabigatran, Apixaban, Everolimus,
Vincristine, Nilotinib, Afatinib, Bosutinib, Trabectedin, Ombitasvir,
Simeprevir, Dasabuvir, Paritaprevir, Topotecan, etc. are
administered concurrently.
